Improvement in car-brakes



W, C. ALLISON.

Car-Brakes.

N0I 157,776I Y Patented De. 15, 1814.

WILLIAM (l. ALLISON, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO HIMSELF, J. W. ALLISON, AND T. E. ALLISON, OF SAME PLACE.

IMPROVEMENT IN CAR-BRAKES.

Specification forming part of Letters Patent No. l57,776, dated December 15, 1874; application tiled October 22, 1874,

To all whom t may concern:

Be it known that I, WILLIAM G. ALLIsoN, of Philadelphia, Pei'insylvania, have invented an Improvement in Car-Brakes, of which the following is a specification:

The object of my invention is to maintain the shoes of braking apparatus in the same vertical position in relation to the wheels, whether the 'car is lightly or heavily loaded, thereby overcoming difculties in operating the brakes, as explained hereafter.

This objectI attain by suspending the brakeshoes from the xed bolster, as shown in the accompanying drawing, in Which- Figure l represents a sectional view of a truck with my improvement, and Fig. 2 a detached view of the bracket from which the brake-shoes are suspended.

A represents one of the side frames of the truck, the two frames being connected to gether by cross-bars and by the central fixed bolsterD in the usual manner, and having the ordinary axles E and iianged wheels F. On

. springs H, bearing on the iixed bolster, rests the movable bolster D', to which it has been usual to suspend the brake-shoes G, so that the vertical position of the latter varied in accordance with the load on the car.

In applying the brakes on a heavily-loaded car the shoes would be necessarily depressed, and a greater movement would have to be imparted to the brake-lever I than if the shoes occupied a more elevated position when the car is relieved of its load; hence adjustments of the braking-tackle to suit the different positions of the shoes became necessary.

Another evil resulting from the suspension of the brakeshoes from the movable bolster is this: In-arresting a heavily-loaded car the shoes would be applied low down to the peripheries of the Wheels, and when the car was relieved of part of its load the recoil of the springs to raise the body of the car would also be exerted to elevate the shoes, which would consequently be so tightly jammed to the Wheels that an excessive strain had to be iinparted to the braking-tackle, and the releasing of the brakes was consequently a dificult matter.

These defects are obviated by securing brackets a to the iixed bolster D, and connecting` the brake-shoes G to the brackets, by means of links b, as shown in the drawing, so that the said brake-shoes will always retain the same vertical position in relation to the wheels, whether the oar is lightly or heavily loaded.

I claim as my inventionrIhe combination, in a car-truck, ot` a fixed bolster, D, and brake-shoes G suspended from said bolster, substantially as set forth.

nlIn testimony whereof I have signed my name to this specitication in the presence of two subscribing witnesses.

VILLIAM C. ALLISON.

Witnesses:

HARRY SMITH, HUBERT HowsoN. 

